Epson EM07ZS1647F User Manual page 134

4. Troubleshooting (PROFIBUS DP)
♦ Causes of Error
Possible Cause
Electrical surges of
device power supply
Disconnected
terminating resistors
Cable disconnection
Disconnected
connector
Disconnected signal
wire
Loose connector
Loose signal wire
Broken unit
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Examination Method
Measure voltage of device
power supply at the trouble
unit.
→ It should be within the range
of sufficient voltage for
device operation.
(1) Check that terminating
resistors are connected to
both ends of the network.
(2) Measure resistance
between signal wires with
device power supply OFF.
→ Normal: 100 to 120 Ω
Measuring point: Connection
of the trouble unit
For detail, refer to the section
4.2.3.1 Connection Problem.
Check for the connection of
connectors and signal wires.
→ The connectors and signal
wires should be firmly
connected.
Checkpoint: all stations and
all branch taps
For details, refer to the
section 4.2.3.2 Loose
Connector and Signal Wire.
Replace the trouble unit with a
new one.
→ Verify whether the problem
is fixed.
Countermeasure
Check voltage of the device
power supply.
Fix the problem.
How to find the trouble
point:
Remove the terminating
resistor on one end of the
network. The trouble point
is where resistance changes
from 220 Ω .
Connect the connectors and
signal wires again.
Replace the unit with a new
one.
Fieldbus I/O Rev.6